What is a What-Clause in English Grammar?
A "what-clause" is a highly specialized type of noun clause securely anchored by the word what. In advanced English, we utilize it almost exclusively to hyper-emphasize a particular core part of a sentence. It functions like a theatrical spotlight, forcefully drawing user attention to the most critical, important information.
Grammarians officially label these constructed sentences as pseudo-cleft sentences. A normal, everyday sentence is "cleft" (intentionally split in half) to engineer intense focus.
- Normal Sentence: I desperately need a good holiday.
- Cleft Sentence: What I desperately need is a good holiday.
By structurally separating "a good holiday" to the end and isolating it with the verb "is", you dramatically elevate its grammatical impact.
What-Clause Structure and Formula
The standard grammatical architecture involves utilizing a what-clause to act as the subject, linking it directly to the auxiliary verb be, and finishing with the emphasized spotlight information.
[What + S + V] (Subject Block) + be (is/was) + Highlighted Information
In this structural matrix, the word what factually translates to "the specific thing that" or "the specific things that."
| Mundane Normal Sentence | Hyper-Emphatic Sentence with What-Clause |
|---|---|
| I definitively said that. | What I definitively said was that. |
| You desperately need to rest. | What you desperately need is to profoundly rest. |
| He shockingly bought a new car. | What he shockingly bought was a brand new car. |
How to Tell What to Emphasize
Depending on what you want the listener to focus on, the structure fluently shifts.
1. Spotlighting the Object or Noun
This is the predominantly common usage. Keep the subject and verb cleanly inside the what-clause, and push the object to the very end after the "be" verb.
- She genuinely deeply loves reading thick books. → What she genuinely deeply loves is reading thick books.
- I simply want a warm cup of tea right now. → What I simply want right now is a warm cup of tea.
2. Spotlighting the Action (The Verb Itself)
To physically emphasize the action happening, we employ the dummy auxiliary verb "do/does/did" inside the what-clause.
[What + S + do/did] + be + V (Base or Gerund)
- He maliciously broke the large window. → What he maliciously did was securely break the large window.
- She is actively rapidly writing a novel. → What she is actively doing is rapidly writing a novel.
3. The Reverse Inverted Structure
You can actively flip the entire structure backward for a very similar, punchy effect.
Highlighted Information + be + [What + S + V]
- A good holiday is exactly what I fiercely need.
- That is precisely what I boldly said earlier.
How to Handle Verb Agreement
A tricky advanced rule is making sure the verb be logically agrees with the noun it connects to.
- What I need is a new, blue pen. (Singular object → is)
- What I need are some new, blue pens. (Plural object → are)
Exception Tip: In daily conversational speech, it is universally incredibly common for speakers to default to is for totally everything, even plural objects ("What I need is some pens"). However, avoid this in academic writing.
Frequently Asked Questions
Can I emphasize people using a what-clause?
No! What-clauses (and pseudo-clefts) are severely restricted to things, actions, and concepts. If you need to emphasize a human person, you must use an "It-cleft" (e.g., "It was John who broke the window", not "What broke the window was John").
Why don't I use "the thing what"?
Never write "the thing what"! The word "what" inherently contains the word "thing" baked inside its meaning. Writing "the thing what" is redundantly saying "the thing the thing that."
Do I need a comma after the what-clause?
No. Because the what-clause acts entirely as the firm, structural subject of the sentence, placing a comma between the subject and its verb ("is") breaks core grammatical syntax.
Summary & Cheatsheet for What-Clauses
| Sentence Goal Structure | Syntactical Purpose | Working Example Demonstration |
|---|---|---|
| What-clause + be + Info | Stresses the specific information at the tail end. | What I firmly believe is that everyone completely deserves a chance. |
| Info + be + What-clause | Stresses the information right at the beginning. | That is exactly what I firmly believe. |
| What...do + be + Verb | Highly stresses a physical action or event. | What we shockingly did was watch a terribly boring movie. |
💡 The key takeaway: Implement a what-clause (pseudo-cleft) when you desperately want to make one single piece of object or action information visually stand out from the rest. It is your most powerful tool for absolute focus!